Unit Converters · Free tool
Ratio Calculator
Simplify, compare, and scale ratios for recipes, mixing, or design work. This free online ratio calculator works instantly with no signup or download needed.
Simplified ratio
2 : 3
Decimal (A/B)
0.666667
Percentage
66.6667%
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What it does
Simplify a ratio (e.g., 18:24 → 3:4) or solve a proportion where one value is unknown (3:4 = x:12 → x=9). Both modes use GCD-based reduction and exact rational math, so there are no floating-point surprises. Decimals are scaled to integers before reduction.
Useful for recipes, blueprint scaling, aspect ratios, and mixing concentrations. Pair with fraction calculator for arithmetic on reduced fractions, or percentage calculator when you need the ratio as a percent.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/ratio-calculator" width="100%" height="720" frameborder="0" loading="lazy" title="Ratio Calculator" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Pick simplify or solve-proportion mode.
- Enter the ratio values; leave one blank in solve mode.
- Read the simplified ratio or the solved value.
- Check the decimal and percentage equivalents shown below.
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Guides about this topic
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